MCH-K38 - a giant killer!

dr.sah · « **Reply #140 on:** 6 Jun 2016, 12:24 pm »

is there any inside picture of mch k38?

dspringham · « **Reply #141 on:** 8 Jun 2016, 06:01 pm »

Waiting for Casler's reply regarding comparison of K-38 to bridged and unbridged STA-9...

Evoke · « **Reply #142 on:** 8 Jun 2016, 06:18 pm »

Quote from: dspringham on 8 Jun 2016, 06:01 pm

Waiting for Casler's reply regarding comparison of K-38 to bridged and unbridged STA-9...

Hello, D -

I just bought the K-38 and had heard the STA-9 as well... Jason explained this BRILLIANTLY in a previous post in case you didn't happen to see it... Here it is copied. I'm sure JC will be able to add his thoughts - but we both referred to this a lot at THE Show...

Mark

"After consulting with the chief engineer, I have more details and very interesting information.
[/size][/size]A class-D amp product is consisted of three main components:[/size]Preamp Stage, Class D Stage, Power Supply(note that this Preamp Stage is not the volume control preamp, but an integral front-end of the Class D amp design)Preamp Stage design is made of (A) Op Amp or discrete transistors and in NuPrime's designs there two types: (B)ULCAM (Ultra Linear Class A Module) and (C)SECAM (Single Ended Class A Module)Practically all the amp products on the market use Op Amp for preamp stage. Only a few very high end products use discrete transistors design. This is hard core analog design. Tube or solid state amp is basically one BIG (giant size) transistor. Now you can see why we could reproduce tube or solid state sound, while keeping the advantage of class D speed and dynamic. Class D power stage design can be Half Bridge (H) or Full Bridge (F)Power supply can be Switching (S) or Linear (L)Now here's where things get really interesting.IDA-16 = A+H+S (Op Amp + Half Bridge + Switching) for clean, fast, and powerfulST-10 = A+F+L for clean, fast, smooth and refinedIDA-8 = B+H+L for a little more warmth and fastSTA-9 = C+H+L for tube-like sound, warmth, and fastK-38 = C+B+H+S There are more combinations that we can do here: C+H+S or C+B+F+L or C+B+F+SChief engineer said there could be literally unlimited number of topologies using transistors for the preamp stage, but to get something good is very tedious work. I think NuPrime is the only company in the world that can offer this type of ultra high end custom design at budget price.We plan to introduce Custom Audio (rack mount) very shortly for customers who order large number of channels (> 10) to do custom selection. For example, you might want to have 10 channels of IDA-16 and STA-9 combo sound, but only need 50W per channel (multi-room high end back ground music). We can mount the preamp stage of STA-9 with the Class D power stage of IDA-16, and one 500W SMPS. Or if you are a speaker company, we can custom design amp module for your active speaker."

gregfisk · « **Reply #143 on:** 9 Jun 2016, 03:15 am »

Quote from: dspringham on 8 Jun 2016, 06:01 pm

Waiting for Casler's reply regarding comparison of K-38 to bridged and unbridged STA-9...

This is what I would like a comparison of, even thou I don't need the power output of the K-38 or the STA-9 as bridged monos.

Evoke · « **Reply #144 on:** 9 Jun 2016, 03:23 am »

Quote from: gregfisk on 9 Jun 2016, 03:15 am

This is what I would like a comparison of, even thou I don't need the power output of the K-38 or the STA-9 as bridged monos.

I didn't think the power was needed too - until I hear it. So I heard 100 watts then 200 and then 400 (rough numbers)... None of them were louder - well the two larger ones were - but the point was the dynamic capability. And there is / was much more "weight" in the delivery of the music. So is it needed - that's up to you. I can only speak of EDDIE - he sounds better with the 200 and 400 watt amps.

gregfisk · « **Reply #145 on:** 9 Jun 2016, 06:06 am »

Quote from: Evoke on 9 Jun 2016, 03:23 am

I didn't think the power was needed too - until I hear it. So I heard 100 watts then 200 and then 400 (rough numbers)... None of them were louder - well the two larger ones were - but the point was the dynamic capability. And there is / was much more "weight" in the delivery of the music. So is it needed - that's up to you. I can only speak of EDDIE - he sounds better with the 200 and 400 watt amps.

I do get what you are saying, I have heard that with my 86db speakers in spades before. I'm now only running the top end of another pair of my speakers which consists of a midrange and tweeter and they are 97db efficient.They can run on pretty low wattage amps. But even with them I have noticed a much better grip on the midrange driver with bigger amps. And I do like to crank it up on occasion and that's when I really notice it.

I suppose if the amps sound good enough it doesn't matter how big they are, then it comes down to what you think you need or how much you want to spend.

Evoke · « **Reply #146 on:** 9 Jun 2016, 02:14 pm »

Quote from: gregfisk on 9 Jun 2016, 06:06 am

I do get what you are saying, I have heard that with my 86db speakers in spades before. I'm now only running the top end of another pair of my speakers which consists of a midrange and tweeter and they are 97db efficient.They can run on pretty low wattage amps. But even with them I have noticed a much better grip on the midrange driver with bigger amps. And I do like to crank it up on occasion and that's when I really notice it.

I suppose if the amps sound good enough it doesn't matter how big they are, then it comes down to what you think you need or how much you want to spend.

Yes, Greg - I failed to add that high current amps don't always have high wattage ratings. And I don't want to make an absolute statement, but from my experience that plays a major role in speaker performance - especially with your 97 db efficiency! If you have some time google around for some high end powered studio monitors and you can see what kind of power they use for woof / mid / tweet. It's very interesting.

jonbee · « **Reply #147 on:** 9 Jun 2016, 02:39 pm »

I have a stack of ST-10 and DAC-10H arriving today. I'll be comparing it in stages to my NAD M51/tweaked N-Core NC-400, which uses no preamp other then the M51.
I love the sound I have now, with no reservations at all on sound quality, but the features of the NuPrime stack, including analog inputs, a headphone amp, 12V system trigger, small size and price make it an appealing package for me.
If I "break even" on sound quality I'll call it a win.
Should be interesting. I'll try to report my initial findings this evening.

MttBsh · « **Reply #148 on:** 9 Jun 2016, 02:46 pm »

Quote from: jonbee on 9 Jun 2016, 02:39 pm

I have a stack of ST-10 and DAC-10H arriving today. I'll be comparing it in stages to my NAD M51/tweaked N-Core NC-400. Should be interesting.

jonbee - I am about to order an ST-10 also, please share your impressions when you get a chance! Thanks

John Casler · « **Reply #149 on:** 9 Jun 2016, 03:59 pm »

Quote from: dspringham on 8 Jun 2016, 06:01 pm

Waiting for Casler's reply regarding comparison of K-38 to bridged and unbridged STA-9...

Hi dspringham,

I think we talked on the phone "pre-show", so my memory is foggy, and I couldn't find any of your previous posts on the STA-9.

But I did see that you are looking for the transparency and detail.

I have heard the STA-9, the ST-10, and the K-38.

In my system, the K-38 and the ST-10 are the "detail" champs.

That said, the STA-9 is not necessarily "less detailed", but slightly less forward. I still hear the same highs, but they are slightly further back in the soundstage.

And of course, the STA-9 has the warmer tube-like sound with more even order harmonics.

Let me know if I missed anything we discussed as 5 day at the show fried my brain

Hugh · « **Reply #150 on:** 9 Jun 2016, 04:34 pm »

I've got to stop by your place for a listen.

dspringham · « **Reply #151 on:** 9 Jun 2016, 10:34 pm »

Thanks John,

Yep, that was me (from Canada) you spoke with the other week.

I've been considering the ST-9 and 10 and have decided to pick-up a (preowned) DAC 10-H/ST-10 stack. My speakers (Daedalus Audio) are non-aggressive in the top end and slightly towards the warm side of things so I thought the neutrality and resolution of the ST-10 would be a good match. Also, I already have an excellent digital front end (Sony HAP-Z1ES with RWA Stage 3 mods) with battery powered tube output stage with which I will feed the analogue input of the DAC 10. The smoothness of the tubes should be a good match for the high resolution ST-10.

I only wish the DAC 10 had a balanced analogue input so I wouldn't have to do an external balanced/single-ended adapter at the output of my source.

Looking forward to trying the Nuprime DAC section as well.

jonbee · « **Reply #152 on:** 10 Jun 2016, 12:55 am »

Just got the ST-10/10H and am checking 'em out!
I swapped my newly arrived ST-10 for my tweaked N-Core NC-400 for starters. I'm powering my Von Schweikert VR-5 HSE, a 91 db/m sensitive 4 ohm design. First up, I'm using my NAD M51 DAC as source, w/ Zenwave D4 balanced ICs.
I'm very pleased with the sound. There are clearly differences in sonics- the N-Core has a more forward top end- it pushes the detail a bit more. The ST-10 has a more relaxed sound overall, with a detailed yet easy top end. Detail is very close; the N-core might have a small edge, with a bit more air on top, but the more forward upper range could be responsible for that. The bottom end of the ST-10 is similarly deep and powerful, but I give it the edge in control, which is remarkable as the N-core is the best I've had in that area.
The overall impression of the amp is very enjoyable- it lets the sonic fabric through with a very natural sounding soundstage. Very nice indeed. Certainly in the same class as the N-Core, but with a different, more relaxed flavor.
I just moved the 10H into place, and it is a great match for the amp, perhaps better synergy than the NAD. Very detailed and open; great soundstage depth and width. Very clean bass. Once again, an easier sound than I had with the M51/N-Core. I think a little bit more air and silkiness at the very top would be an improvement, but that is really nitpicking. The more I listen to the combination the more I admire the really wonderful soundstage presentation and overall tonal balance. The music is just plain enjoyable. Very cool remote, too.
I'm very pleased. As always, matchups are key to this hobby, but this combination is very satisfying, and at a very attractive price. The best, cost-no-object? I'm sure not, but these deliver the goods with very little getting in the way of the music.

jonbee · « **Reply #153 on:** 10 Jun 2016, 02:58 am »

Quote from: dspringham on 9 Jun 2016, 10:34 pm

My speakers (Daedalus Audio) are non-aggressive in the top end and slightly towards the warm side of things so I thought the neutrality and resolution of the ST-10 would be a good match.

I owned DA-RMA v2 last year, and I think they will work very well with these. I think they are sonically of the same cloth. The ST-10 is not warm but offers a very natural, unforced view of the music.

JackD · « **Reply #154 on:** 10 Jun 2016, 03:05 am »

jonbee

I completely agree with your assessment of the ST-10 so fair. Mine is singing happily with my Nola KO's fronted by the Modwright LS-100. I ran it briefly in the other system with the DAC-10 and the Spatial M3 Turbo S's and it sounded fine there too. A really good pair of components at a fair price.

dspringham · « **Reply #155 on:** 10 Jun 2016, 03:44 pm »

jonbee,

Looking forward to your impressions of the DAC-10H in view of the fact that you have your old standard NAD M51 up for sale.

With your DAC 10 comments can you also provide the details of your digital source and how you are connecting (USB, SPDIF etc.)

Regarding your ST-10/ncore 400 comparison, you mentioned the ncores had been modded (Ric Schultz cap mod). How do you think the ST-10 would compare to a stock NC400 (I know this might be straining your auditory memory).

Can you also comment on the DAC 10/ST-10 "stack" as a complementary pair in terms of SQ, versatility and functionality. It seems to me that they represent a high value package.

Regards,
Dave

WHOOPS! Didn't see the most recent comments in your modified post. Thank you

dspringham · « **Reply #156 on:** 10 Jun 2016, 03:53 pm »

jonbee,

One other thing. Are you running balanced or single ended to the ST-10?

Also, have you tried running the M51 fixed outputs to the DAC-10 in order to assess the analogue throughput of the DAC-10?

jonbee · « **Reply #157 on:** 10 Jun 2016, 04:45 pm »

Quote from: dspringham on 10 Jun 2016, 03:53 pm

jonbee,

One other thing. Are you running balanced or single ended to the ST-10?

Also, have you tried running the M51 fixed outputs to the DAC-10 in order to assess the analogue throughput of the DAC-10?

Balanced.
No, just used the variable outputs of the NAD.
Still listening happily. This is a great stack. I do think there is synergy to be had with the 2 units together.
NuPrime's claim of superior soundstage depth and width is certainly true. Just huge. My earlier thoughts on the top end may be premature. Compared to the N-Core they are more relaxed on top, but the N-Core always seemed just a bit bright to me, so maybe the NuPrime is just right? I'm sure they will be here a long time. They sure check off all my boxes.

jonbee · « **Reply #158 on:** 13 Jun 2016, 11:42 pm »

Just an update- I've listened to the ST-10/10H for a few days, an I do like it better than the NAD M51/modded N-core Nc-400 I'd been happily using for the last 3 years. The tonality of the ST-10 is equally detailed but more laid back on top than the N-Core, which necessitated I turn up the ambience tweeters on my Von Schweikerts a bit, but the upper mids are more relaxed and natural on the ST-10. I should note that the VSs are a little laid back on their own, so this observation wouldn't necessarily apply to other speakers. Bass range is a bit better defined, too. No downside I've heard.
I still like the N-Core a lot, and moved it to my office, where it sounds great.
The N-Core cost about $2200 in parts, plus my labor. At $1600 the ST-10 equals or betters it and is the biggest amp bargain I've heard, and with the 10H it offers really fine performance that may well be impossible to beat for the $.
It's hard to imagine it being that much better modded, but I'm thinking about the TDSS upgrades. More later if I do that.

John Casler · « **Reply #159 on:** 13 Jun 2016, 11:47 pm »

Quote from: jonbee on 13 Jun 2016, 11:42 pm

Just an update- I've listened to the ST-10/10H for a few days, an I do like it better than the NAD M51/modded N-core Nc-400 I'd been using. The tonality of the ST-10 is more laid back on top than the N-Core, which necessitated I turn up the ambience tweeters on my Von Schweikerts a bit, but the upper mids are more relaxed and natural on the ST-10. Bass range is a bit better defined, too. No downside I've heard.
I still like the N-Core a lot, and moved it to my office, where it sounds great.
The N-Core cost abut $2200 in parts, plus my labor. At $1600 the ST-10 at least matches it and is the biggest amp bargain I've heard, and with the 10H it offers really fine performance that is hard to match for the $.
It's hard to imagine it being that much better modded, but I'm thinking about the TDSS upgrades. More later if I do that.

It may be possible that "some" of that quality you like is due to a higher carrier frequency (around 550khz-600khz) of the NuPRIME.

I looked around, but didn't see the stat for the N-core. Have you read anywhere what it is?